A combined centrifugal force (X+Y) is produced in a container (8) when the container on a distal end of an arm (3) circles around a main rotary shaft (2) of the arm and simultaneously rotates on its own rotary shaft (6) in harmony with the circling motion thereof. The starting ingredients for a food/beverage product are received in the container and subjected to the combined centrifugal force, so that the ingredients are processed into the food/beverage product. Various types of elements such as a sieve-like capsule member (10) detachably mounted in the container (8), a small concave-convex portion provided in an appropriate inner surface of the container (8), and/or a raised floor member (15) provided with a pair of a radial blade (12) and its corresponding radial slot (14) detachably mounted in the container are used to enhance the processing operation.